78 RPMs and Cylinder Recordings
The Great 78 Project! Listen to this collection of 78rpm records and cylinder recordings released in the early 20th century. These recordings were contributed to the Archive by users through the Open Source Audio collection. Also the Internet Archive has digitized many.
Artists available here include Ada Jones, Caruso, Eddie Cantor, Edison Concert Band, Harry MacDonough, Len Spencer, Paul Whiteman, and many others.
The Almost Complete 78 RPM Recording Dating Guide by Steven C Barr has good information about the record companies.